Electric switch mechanism



Sept. 6 19490 NEWELL 2,481,333

ELECTRIC SWITCH MECHANISM Filed April 27, 1946 2 Sheets-Sheet l inventor 36 Haber L. Nev/en,

His Attorney p 1949- H. L. NEWELL 2,481,333

ELECTRIC SWITCH MECHANISM Filed April 27, 1946 2 Sheets-Sheet 2 Inv e140 or v Hebe? L. Nev/en b W WM His Attorney.

Patented Sept. 6, 1949 ELECTRIC SWITCH MECHANISM Heber L. Newcll, Fishkill, N. Y., assignor to General Electric Company, a corporation of New York Application April 27, 1946, Serial No. 665,501

Claims.

The present invention relates to electric switch mechanisms which comprise a number of switches actuated in a desired sequence to open and close electric circuits. Such switch mechanisms are used in connection with automatic control mechanisms and the like. In the present instance, I have shown my invention as being embodied in a switch mechanism for use with an automatic washing machine. It is to be understood, however, that this is only by way of example.

One object of my invention is to provide a switch mechanism which is simple in structure, compact, and relatively small in size.

A further object is to provide a switch mecha" nism which while small and compact is capable of controlling a maximum number of circuits.

Other objects and advantages of my invention are pointed out in the course of the following specification and for a consideration of what I believe to benovel and my invention, attention is directed to the following specification and to the claims appended thereto.

In the drawing, Fig. 1 is a top plan view of a switch mechanism embodying my invention; Fig. 2 is an end view thereof; Fig. 3 is a sectional view taken on line 33, Fig. 1; Fig. 4 is a sectional view taken on line 4-4, Fig. 3; Fig. 5 is a detail sectional view on a larger scale taken on line 5--5, Fig. 3; Fig. 6 is a perspective view of a part of the mechanism; Fig. 7 is a perspec tive view of a part of the mechanism, and Fig. 8 is a sectional view taken on line 8-8, Fig. 3.

Referring to the drawing, I indicates a base plate or bracket, the general outline of which is best shown in Figs. 6 and 8. Supported on it is a fixed shaft 2 on which is journaled a cam drum 3, the hub 4 of which is located between base plate I and a top plate or bracket 5. The general outline of top plate 5 is best shown in Fig. 1. Cam drum 3 is constructed to provide at its surface a series of axially spaced circumferential cams each comprising lands and depressions, eight being shown in the present instance. It may be of any suitable construction. As shown, it comprises a barrel 6 provided with eight axially spaced annular grooves l. Wrapped around the barrel is a mask 8 formed from a sheet of thin metal provided with eight rows of circumferentially extending slots 9 which stand in line with grooves 1. Thus the surface of mask 8 forms the lands of the annular cams and the slots 9 define the depressions. This cam drum construction is not claimed herein. It is more fully disclosed and claimed in my applica- 2 tion Serial No. 665,500, for cam, filed of even date herewith and assigned to the same assignee as my instant application. At its upper end, cam drum 3 is provided with a head ill on the top surface of which are indicia as shown in Fig. 1.

Fixed to the lower end of hub s is a pinion 5! which meshes with a gear I? carried at one of a shaft l3 journaled in an opening in plate l. On the other end of shaft I3 is a gear M which meshes with a pinion IE on a hub is journaled on the lower end of shaft 2 beneath base plate I. Hub I6 is connected to a gear l! through a ball clutch comprising a disk is on huh I 5 having in its periphery (Fig. 5) notches H9 in which are positioned balls 2'] biased by springs 2! into engagement with the inner surface ai a flange 22 integral with gear ll. Meshing with gear I? is the driving pinion 23 of a suitable electric timing motor 24. Timing motor 24 drives cam drum 3 through the gearing and the ball clutch, the balls 20 being wedged between flange 22 and the adjacent notch surfaces when gear I! is turned in a clockwise direction as viewed in Fig. 5. At 25 is a hand wheel for turning the cam drum independently of the timing motor. The hub of hand wheel 25 is pivotally mounted on hub I5 and carries pins 26 which project into notches l9 and engage their forward walls. When hand wheel 25 is turned in a clockwise direction (Fig. 5) pins l6 engage disk is and rotate it and hub It to turn drum 3 at reduced speed through gears l5, M, iii and II, the ball clutch permitting the hand wheel to turn independently of timing motor 24. Backlash between pins 26 and the adjacent notch surfaces is taken up by a spring 21 positioned in a notch in disk ll! between a pin 28 on hand wheel 25 and the adjacent surface of the notch. With the foregoing arrangement it will be seen that the cam drum 3 may be turned either by the timing motor or by the hand wheel. Timing motor 24 is supported on brackets 29 carried by base plate I.

Positioned between base plate I and top plate 5 are one or more circuit closer bases 30, two being shown in the present instance, formed from suitable insulating material. The bases 38 are alike in structure. As best shown in Fig. 7, each has a flat straight outer end wall 3! and a re-entrant or V-shaped inner end wall 32. Extending across the center of the base is a rib 33 which divides the upper side of the base into halves. Similarly, the rib divides the lower side of the base into halves. Thus the base has four 3 sections which are alike, two on top and two on the bottom. These are designated A, B, C and D. Referring to section A, which will be described, it is provided with recesses which define two spaced posts 34 and 35 between which is positioned a column spring 35 having contact buttons 31. At its outer end column spring 35 is provided with a contact blade 33 which projects beyond end wall 3!. On opposite sides of column spring 36 are contact blades 39 and 40, the outer ends of which project beyond end wall 3| and the inner ends of which are positioned in angularly shaped grooves defined by posts and projections M. On blades 39 and 40 are stationary contact buttons adapted to be engaged by contact buttons 3'1. The outer end of column spring 36 is fixed rigidly in post 35; the inner end may slide axially in post 34. It is held in compression in wave form by a short metal spring strip '42 in post 34 against which it abuts and is biased to .a position in engagement with one stationary contact by a spring 43 positioned between the column spring and the inner end of a recess in base 39. Engaging the column spring at a point opposite spring 43 is a nose 44 of insulating material which is carried by the free end of anactuator 45 pivoted at 46 on one side of an ear 4'! projecting from base 30. It is held on its pivot 'by a U-shaped spring clip 48. Actuator 45 has ,a projection or corner 45 which rides on the surface of the cam drum in line with one circular cam. When corner 49 is in one of the slots 9 of a circular cam, the contact button on the column spring engages the contact button of contact blade at When corner 49 rides up onto the surface of the cam, it moves the column spring to cause contact button 31 to snap out of engagement with the contact button on contact blade 40 and into engagement with the contact button on contact blade 39.

The planes of sections A, B, C and D are offset relatively to each other so that the four actuators 45 are positioned to stand in line each with a circular cam on the cam drum. (See Figs. 2 and 6.)

The two bases 30 are positioned one on the other. They are provided with intermediate and outside cover plates 50. The outside cover plates are held by screws 51. The intermediate cover plates are clamped between the two bases 30. The

bases 39 are held between base plate I and top plate by bolts 52.

Referring to Fig. 6, it will be seen that when the bases 3e are clamped together between base I and top plate 5, the eight actuators 45 stand in eight axially spaced planes in line with the eight cams on the cam drum. At 53 is a guide bracket, U-shaped in cross section which is attached to base plate I and top plate 5 at its ends. It is provided with slots '54 in which actuators #5 are guided and held in line with the cams.

In addition to the contact blades already described, there is provided an additional pair of contact blades 55 to the inner end of which the leads of the timer motor 24 are connected. Contacts 55 are carried by a block of insulating material 56 clamped between base plate I and the adjacent base 30, base plate I being provided with an opening 5'! through which the inner ends 58 of blades 55 project.

The switch mechanism, which in substance is a multi-contact plug switch, is adapted to be plugged into a suitable plug receptacle (not shown) which may be mounted on the washi g machine or other machine to be controlled and have the wiring connected to its contacts. Positioned in ears 60 on base plate I is a rod 6| having a head 62 at its outer end to receive an operating tool and a threaded section 63 at its other end adapted to enter a threaded opening in a plug receptacle. The plug switch may be positioned in line with the plug receptacle to which it is to be connected and then, by turning rod GI, drawn into the plug receptacle to make connection; and it may be backed from engagement .with the plug receptacle by turning the rod in the opposite direction. On top plate 5 is a T-shaped ear 64 which, when the plug switch is in place on a receptacle, may interlock with an adjacent wall.

Each section A, B, C and D is a switch unit comprising a movable switch contact and two fixed switch contacts and each contact is provided with a contact blade by means of which it is connected into the control circuit. Also the timing motor which is a part of the switch mechanism is provided with two contact blades through which it is connected into the control circuit. By this arrangement, there are no wires connected permanently with the switch mechanism. This has the advantage that it enables the switch mechanism to be quickly and easily at tached to and detached from the machine without having to attach or detach any lead wires.

By reason of the offset arrangement of the switch units and the re-entrant end in which the cam drum is positioned, there is provided a relatively small compact mechanism which at the same time is simpl in structure and capable of being manufactiued and assembled at low cost. The switch mechanism may be utilized in connection with various control systems since if for any particular control system certain contacts are not needed, they may be omitted without change in the general structure.

In the present instance, two bases 30 are illustrated, However, the mechanism may be built with only a single base 30 or with more than two.

What I claim as new and desire to secure b Letters Patent of the United States is 1. A switch mechanism comprising a flat base of insulating material having a plurality of-recesses therein, a plurality of switch units each carried by the base within a respective one of said recesses and comprising fixed and movable switch contacts, each said fixed and movable contact having a conducting blade projecting beyond an end of the base for connection with a plug receptacle, actuators for the movable contacts, and a cam drum externally of said base for moving said actuators.

'2. A switch mechanism comprising a fiat base of insulating material, a plurality of recesses in opposed faces of said base, a plurality of switch units each carried bythe base within a respective one of said recesses and comprising fixed and movable switch contacts, each said fixed and movable contact having a conducting blade projecting beyond an end of the base for connection with a plug receptacle, actuators for the movable contacts, and a cam drum supported externally of and in fixed relation to said base for moving said actuators.

3. A switch mechanism comprising a body of insulating material having a straight outer .end and divergent leg portions extending therefrom to define a re-entrant inner end, said body being divided medially into two top sections and two bottom sections, and circuit closing means cary each section comprising column springs extending lengthwise of the sections held at their ends in wave form, fixed contacts adapted to be engaged by the column springs, electrically conducting blades connected to the outer ends of the column springs and to said fixed contacts projecting beyond the straight outer end of the base, actuators pivotally afiixed at the extremities of said leg portions and projecting into said reentrant inner end and through openings in the base into operating engagement with the column springs, said actuators being arranged in separate planes parallel to the plane of the base, a cam drum rotatably mounted within said reentrant end and engaging with the pivoted actuators to operate the same, and means for rotating said drum.

4. A switch mechanism. comprising a body member of insulation material having divergent leg portions extending from a relatively wide base; mutually cooperating fixed and movable contacts disposed within recesses in said leg portions, each said fixed and movable contact having means external of said base for connection into an electric circuit; actuators for the respective movable contacts extending from the extremities of the leg portions into the space bounded thereby; a cam drum disposed at least in part within said space intermediate said actuators and cooperating therewith to efiect circuit-controlling operation of said movable contacts; means for journalling said cam drum; and means for rotating said drum.

5 A switch mechanism according to claim 4, in which the respective actuators are disposed in different planes.

HEBER L. NEWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,926,857 Moister Sept, 12, 1933 2,176,195 Bassett Oct. 17, 1939 2,250,168 Pfleger July 22, 1941 2,262,306 Thompson Nov. 11, 1941 

